You may think that site assessment is an unnecessary cost until you witness a crew accidentally hitting an unmarked gas line on a jobsite, or experience a three-week delay due to an emergency geotechnical report because the foundation design was incorrect. Every construction delay can be traced back to something that should have been identified before breaking ground.
Start with a site feasibility study before anything else.
Before you commission surveys or borings, you need a clear-eyed answer to one question: can this site actually support what you’re proposing? A site feasibility study considers the physical and legal constraints of a parcel in relation to the proposed design. This includes an approximation of grading requirements, the availability of utilities, potential zoning violations, and whether the lot’s geometry can contain the building footprint plus required setbacks in the first place.
Not doing this – or doing it in name only – is how developers find themselves halfway through design development before they realize the project simply isn’t going to work on this site. Then it’s not just the redesign that’s painful, it’s the capital loss of having carried that land for half a year too many.
A proper feasibility evaluation to see if your site works will leave you with the deal-breakers, but they’ll be your deal-breakers, caught early.
Execute geotechnical borings before the design gets locked in.
Soil conditions are something you can’t see from the surface, and they impact some of the most expensive parts of your building.
Geotechnical investigation (drilling borings to get soil samples for lab analysis) helps you understand soil bearing, depth to bedrock, compaction, and whether you’re going to be digging in the water table.
All of these factors directly relate to what type of foundation you’re building. A site with good bearing soil and a low water table might pencil out with a simple spread footing. Lose two of those conditions and you could need a deep foundation system with driven piles or helical anchors. For a mid-sized building, you might be looking at a $200k+ delta in foundation cost between those two scenarios.
The trap that teams fall into is that the geotech process is often scheduled too late. By the time the boring logs come back and the structural engineer’s eyes bug out at the new L: D ratio needed to support the core, it’s too late to make any real redesigns. The project team for every other discipline just has to bite the bullet and start over on the portions of construction that are already drawn.
Instead of thinking of borings as a point to confirm your assumptions after the fact, conceptual borings with few enough points to all fit on a single page should be part of the schematic phase.
Map utilities to a depth, not just a location.
Information provided by public locating services indicates the approximate location of underground utilities. Because this information is generally based on information from utility companies’ “as-built” records, the data can lack accuracy and reliability. Consequently, utility conflicts are a responsibility that falls on contractors. This creates a serious risk of injuries or fatalities during excavation and construction, as well as numerous utility damage claims.
To mitigate this risk, many prudent owners are now requiring the use of Subsurface Utility Engineering (SUE) services during the design phase of their projects. SUE utilizes surveying and geophysical technology to identify the location of all underground utilities, thereby reducing conflicts, utility delays, claims, design changes, utility relocations, added construction time, and overall risk. This is also where early collaboration between civil engineering and site design pays off most visibly – hiring a multidisciplinary firm like BC Engineering Group allows developers to integrate landscape architecture with technical site planning from the start, so aesthetic goals align with the engineering constraints rather than competing with them.
Build a high-resolution topographic model early.
Topographic surveys provide precise elevation data on the existing surface of the site – each grade change, drain channel, retaining wall, and grade break. This data is what the grading plan is based on, and the grading plan is how the civil engineer determines cut-and-fill volumes.
Cut-and-fill balance matters because soil is heavy and moving it costs money. If your grading design calls for 10,000 cubic yards of cut but only uses 4,000 cubic yards as fill, guess what: you’re exporting 6,000 cubic yards off site. At current haul rates, that’s a big unbudgeted change order.
Topographic surveys generated from old or low-res base data give you a grading plan that looks just great on the monitor – but doesn’t work in the field, where real-world conditions that you didn’t document become the change orders you didn’t count on.
Design drainage before the site plan is final.
Water flows where gravity takes it and it does not change its path. When you perform a hydrological analysis you can understand what will be the saturation level, the erosion pattern, where water will be retained and where it could get contaminated. It is important to understand the existing dynamics, not only for the safety of your site but also to ensure you are compliant with the building requirements in your area.
Most probably you will be asked to maintain the same runoff from your site post-construction as it did pre-construction. It is very common to have that obligation and that essentially means providing some artificial storage for water to cover the difference in time between the water reaching the sewers and the new construction needing to use them.
For all these reasons, both for making the project feasible and for ensuring it is sustainable it is very important that early in your project you task your site engineer with the design of the storage, identify where the water flows on and off your site, and design the necessary routing and storage solutions.
Finally, remember to never wait to involve a storage engineer until you have completed your grading plans, in all likelihood, you will realize that you need to change them significantly to accommodate the new requirements or that you will have to tinker with the layout and lose floor area in the process.
Review easements, setbacks, and rights-of-way before placing structures.
A piece of land can appear to be buildable on a basic boundary survey and yet be almost entirely unbuildable due to legal encumbrances that are invisible unless you actively seek them out. Utility easements, drainage easements, access rights-of-way, and shared maintenance agreements can all preclude the placement of permanent structures.
These are not suggestions. Building a structure over a utility easement means the utility company has the legal right to remove it if they need access. Walking straight out of compliance with a setback requirement and onto your neighbor’s land requires cash from your pocket, and a lot of it, every month you do so. And going to the city and asking for a variance will take time, likely more time than you’re planning to stay on schedule and within budget, and may yet be futile.
Your construction lender should not be the first person who discovers that your building footprint runs over a listed easement. Obtain all legally recorded documents during the survey phase and heed their constraints.
Address environmental history and tree protection before mobilization.
Two types of evaluations that are often underestimated as minor concerns are actually critical project risks: environmental history, and site vegetation.
A Phase I Environmental Site Assessment looks at the past use of a property and its vicinity to determine whether it is plausible that the site has been contaminated with hazardous material: this is an issue for any project with previous industrial, commercial, or agricultural activity. If the Phase I suggests there may have been a problem, the Phase II testing begins. If, instead, the bulldozer uncovers contaminated soil with no prior assessment, all work stops. The site is declared a regulated waste. The schedule expands while environmental consultants and regulators become part of the project, and the expense of remediation is added to a budget that didn’t expect to pay for it.
The arborist report is the biological protection analog to the environmental review. Many municipalities protect specific species of trees – which in many cases also means their root structures. A tree that is obviously outside the construction zone and therefore presumed safe may have extensive roots that extend well into the construction zone. Heavy machinery pressing down on roots over a root protection zone can kill the tree. The fine for unauthorized tree removal or damage can also be astronomical.
Draft the SWPPP before ground breaks.
The Stormwater Pollution Prevention Plan is a federally required erosion and sediment control plan for construction sites above a minimum disturbed area threshold. It specifies where silt fences go, how stockpiles are managed, where concrete washout areas are located, and how the site is stabilized during and after grading.
Failing to have a compliant SWPPP on file before construction begins is a regulatory violation that can result in a stop-work order. Getting that order lifted takes time, and construction has to sit idle while it happens. More importantly, violations can follow a company through future permit applications.
The SWPPP isn’t bureaucratic friction. It’s the document that lets you run a grading operation through a wet season without shutting down.
The pattern across all seven steps is the same: information gathered before construction costs a fraction of what the same information costs to deal with mid-project. Change orders are the mechanism through which unplanned discovery translates into unplanned expense – and most of them trace back to something a thorough site assessment would have surfaced. The work isn’t glamorous, but it’s what separates projects that finish on schedule from the ones that don’t.
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